isNumber = function (e) {  
	if ($.browser.msie) {  
		if ( ((event.keyCode > 47) && (event.keyCode < 58)) ||  
			  (event.keyCode == 8) ) {  
			return true;  
		} else {  
			return false;  
		}  
	} else {  
		if ( ((e.which > 47) && (e.which < 58)) ||  
			  (e.which == 8) ) {  
			return true;  
		} else {  
			return false;  
		}  
	}  
}  
